Abstract

Oxyfluoride glass system based on 30ZnF2–20TeO2–(50 – x)B2O3–xSm2O3, (where x = 0, 0.5,
1.0, 1.5, 2.0, 2.5 mol %) were prepared. The density of each glass was measured and the molar volume was
calculated. The model developed by Makishima and Mackenzie (M⎯M) gave reasonable estimation for dif�
ferent constants of elasticity (Young’s modulus, bulk modulus, shear modulus, Poisson’s ratio). Vickers
indentation tests were performed on the series of glass samples. These connections were used to relate the
conventional Hardness. Fracture toughness, dissociation energy and packing density were also investigated.
The relationship between machinability and brittleness of glass materials were studied. Exposition of the
M⎯M model proved to be good for the constants of elasticity of oxyfluoride glasses.